Value of diffusion weighted MR imaging as an early surrogate parameter for evaluation of tumor response to high-dose-rate brachytherapy of colorectal liver metastases

摘要: To assess the value of diffusion weighted imaging (DWI) as an early surrogate parameter for treatment response colorectal liver metastases to image-guided single-fraction 192Ir-high-dose-rate brachytherapy (HDR-BT). Thirty patients with a total 43 underwent CT- or MRI-guided HDR-BT. In 13 these 15 additional lesions were identified, which not treated at initial session and served comparison. Magnetic resonance (MRI) including breathhold echoplanar DWI sequences was performed prior therapy (baseline MRI), 2 days after HDR-BT (early MRI) well 3 months (follow-up MRI). Tumor volume (TV) intratumoral apparent coefficient (ADC) measured independently by two radiologists. Statistical analysis using univariate comparison, ANOVA paired t test Pearson's correlation. At MRI no changes TV ADC found non-treated metastases. contrast, mean increased 8.8% (p = 0.054) while tumor decreased significantly 11.4% < 0.001). follow-up 50.8% 0.027) without significant change values. 47.0% 0.026) inversely 28.6% compared baseline values 0.001; correlation r -0.257; p is promising biomarker prediction in HDR-BT, yet optimal interval between needs be elucidated.